The present invention relates to transportable collective protection systems for decontamination of personnel, and provision of toxic-free areas where injured or infected people can be retained safe from further exposure to nuclear, biological, or chemical hazards (NBC).
Such systems are required for both military and civilian applications. They should be readily transportable by land or air, and capable of being quickly set up with a minimum of personnel, either in contaminated or toxic-free locations. Such systems must come complete with their own power supplies, air filter equipment, air conditioning, lighting, plumbing, and be capable of transport to required sites by aircraft or ground vehicles. In view of the wide range of potential locations for use, fuel for the power supplies must be standard for all areas of the globe.
Performance specifications for such systems require a high standard of materials and design to meet operational requirements in a variety of environments, to safeguard personnel from lethal hazards. This modular collective protection system must be capable of providing relief from psychological and physiological stresses during sustained operations in a contaminated environment due to the wearing of full Individual Protection Equipment (IPE). The system provides the ability to process contaminated personnel through a Contamination Control Area (CCA) into a Toxic Free Area (TFA), as defined in NATO standards, consistent with service decontamination and contamination control procedures.
U.S. Pat. No. 4,707,953 granted Nov. 24, 1987 to Anderson discloses a light-weight expandable shelter providing protection against chemical, biological agents and nuclear fallout. The shelter has a frame of U-shaped ribs spaced and held parallel by a series of reinforcing members. A cover of flexible material resistant to chemical and biological agents is attached to the frame. An airlock is provided at one end of the shelter, through which access can be gained to the shelter. A blower and filter pressurizes the shelter and airlock. Such a shelter is of limited usefulness for personnel protection. Injured or non-ambulatory personnel cannot be passed through the airlock, and the shelter is not capable of modular expansion to provide different areas for specialized activities. This shelter requires numerous personnel to erect it and considerable time for erection to be completed. Disassembling the shelter would also be slow and labor intensive.
Healey, U.S. Pat. No. 4,800,597 issued Jan. 31, 1989 discloses a decontamination shelter consisting of series of small rooms, each large enough for an individual to disrobe, shower, and dress. Each room is separated from the adjacent room by a narrow corridor with a door at one end leading into the corridor from a first room and a door at the opposite end of the corridor giving access to the adjacent room, the corridors being for isolation between rooms.
Canadian patent 2,080,498, issued Mar. 19, 1996, and its U.S. counterpart, U.S. Pat. No. 5,331,991 issued Jul. 26, 1994, disclose a method of establishing and maintaining in sealed tents, an environment which is independent from its surroundings. Filtered air is used to pressurize the tent, and recycled air from the tent is mixed with filtered outside air, when an air pressure is reached , which is higher than a predetermined air pressure. The patent does not disclose entrance and exit details of the tent which impact on the maintenance of pressure within the sealed tent, nor does it address the problems of moving personnel from a contaminated environment to a sealed space, while decontaminating personnel and equipment.
The present invention overcomes all of the limitations of the prior art by providing a transportable collective protection system, which is modular and capable of assembly and operation in both contaminated and toxic free environments, and which permits the decontamination of personnel and equipment in a contamination containment area (CCA), prior to entry into the toxic free area (TFA). The migration of contaminants from the CCA to the TFA is prevented by complete decontamination in the CCA, followed by transfer of decontaminated personnel and equipment to the TFA, while maintaining an over-pressure in the TFA causing a purge of clean filtered air from the shelter through the CCA. The over-pressure is maintained by a blower and filter unit which draws in external air, filters it to remove contaminants, and pressurizes the TFA and CCA to a pressure sufficient to inflate the system to a self supporting state and to purge the CCA and any other minor leakage through closures. Separate electrical generating equipment provides power to run the blower and filter unit as well provides power for lighting, heating, air conditioning, and operation of internal equipment, including fresh water and waste water systems.